cpufreq: tegra186: Initialize all cores to max frequencies

During initialization, the EDVD_COREx_VOLT_FREQ registers for some cores
are still at reset values and not reflecting the actual frequency. This
causes get calls to fail. Set all cores to their respective max
frequency during probe to initialize the registers to working values.

Suggested-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Aaron Kling <webgeek1234@gmail.com>
Reviewed-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>